Interaction Between Drug and Placebo Effect:Randomized Placebo Controlled Trials May Not be Accurate in Determining Drug Effect Size

• Status: Completed
• Trial end date: 2015-10-01
• Target enrollment: 0
• Participant gender: All

Summary

The total effect of a medication is the sum of its drug effect, placebo effect (meaning response of placebo), and their possible interaction. Current interpretation of the results of clinical trials (the gold standard in evidence based medicine) assumes no such interaction. Using a novel cross-over balanced placebo design and caffeine as a model drug, the investigators have recently shown that a negative interaction does exist; suggesting that the size of drug effect as currently measured by clinical trials may not be accurate. Due to the novelty of the findings and their important clinical practice and research implications, they need to be confirmed using another drug; and the size of drug effect measured using the novel design need to be directly compared to that measured using conventional clinical trial design. The results of the study are expected to further our understanding of a widely used medical intervention, i.e., placebo, and help assess the appropriateness of randomized clinical trials in determining the size of drug effect.

• Phase: N/A
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: King Faisal Specialist Hospital & Research Center
• Treatments: Hydroxyzine

Criteria

Inclusion Criteria:

• Age of 18 to 50 years;

• Being healthy,

• Able to abstain from smoking and alcohol

• Medication-free for one week

• Able to reproducibly express oneself using a 100 mm visual analog scale (VAS).

Exclusion Criteria:

• clinically relevant deviation from normal health

• pregnancy or lactation

• hypersensitivity to hydroxyzine or related compounds